Vince Cable is refusing to say if he missed crucial Commons votes on Brexit because he was discussing the creation of a new pro-EU party.
The Liberal Democrats are remaining tight-lipped over their leader’s embarrassing absence, amid a report that he was at a dinner with backers of a new movement.
Sir Vince has said publicly that “new groups may emerge” as Britain’s traditional political system implodes because of bitter splits within the big parties over Brexit.
The Sunday Times reported that he missed Monday’s votes – which saw hardline anti-Brexit Tories force Theresa May into a partial climbdown on her Chequers plan – to meet supporters of a new party.
A Lib Dem source did not deny the report, insisting details of the “private meeting” had to remain under wraps.
The Monday votes saw the prime minister face the biggest rebellion of her premiership, including over her cave-in to prevent the UK collecting tariffs on behalf of the EU unless it agreed to do the same.
She squeaked home by just six votes, after 11 Conservative rebels joined forces with the opposition parties.
Tim Farron, the former Lib Dem leader, apologised after also missing the votes, in order to give a speech on gay sex and Christianity.
In an interview on Friday, to mark his first anniversary as leader of the Lib Dems, Sir Vince gave the strongest hint yet that he was ready to get involved with a new party.
He said he was preparing the Lib Dems for a “radical” shift, saying: “There are large numbers of Labour MPs and quite a lot of Tories who are just bitterly alienated by their own people.
“I can’t see the present system can be kept going. In the new year, new groups may emerge.
“I’m not sure who, or how they’ll be configured. But I predict it is going to happen and my instincts are that if they’re aligned with us on basic values, we can work with them. And that’s what I am campaigning for.”